What was Paul's "revelation" (mentioned in Galatians 2:2)?

You clearly have missed this central revelation. It was all about the Gospel of the Grace of God that had been given in precise details to Paul which he had been proclaiming among the Gentiles. Which was that one could be justified before God by faith alone without observing the Law of Moses. Prior to Paul the Jerusalem apostles were teaching that one had to only believe that Jesus was the long promised Messiah plus they maintained keeping Law rituals. Paul went up to Jerusalem after 14 years to confer with the Jerusalem congregation showing them the Gospel he had been preaching by direct revelation of the risen Christ Jesus and to get their approval; right hand of fellowship (read Acts 15). As to Paul's Christ given Gospel of the Grace of God we all need to believe in (TRUST with the heart) for salvation he details it in:

1 Corinthians 15:1-4 KJV Moreover, brethren, I declare unto you the gospel which I preached unto you, which also ye have received, and wherein ye stand; [2] By which also ye are saved, if ye keep in memory what I preached unto you, unless ye have believed in vain. [3] For I delivered unto you first of all that which I also received, how that Christ died for our sins according to the scriptures; [4] And that he was buried, and that he rose again the third day according to the scriptures:

This is a very hard question and one that will defy any explanation from an orthodox approach.

Paul was converted in 33 or 34 CE, based on the crucifixion occurring in 33. Other dates are suggested but 33 best fits all available facts. Before 32 CE for example, Pilate was secure enough in his position that he would not be swayed by the High Priest no matter how large a mob he gathered.

Paul then spent 3 years in Arabia, probably meaning Nabataea, just to the east. According to Galatians, he returned, stopped by Jerusalem then claims he spent 14 years in Syria and Cilicia. Right here is a sign we have a problem, as Acts has him in Crete and what is now Turkey, contradicting what Paul himself claims. Sometime during this period in Syria and Cilicia, he claims to have received a revelation, which prompted him to go talk to the leaders in Jerusalem, maybe as early as 49 but more likely 50 or later. The exact nature of this revelation is not revealed.

To claim that it was that Gentiles should be included is to ignore the Old Testament which assures that the Gentiles will become God's people in multiple places. Likewise, the Dead Sea Scrolls affirm that Gentiles need not follow Mosaic law, so that is not what the revelation is. Whatever the revelation is, it must be well hidden to modern eyes. It would have been obvious to his listeners, but we are missing some key piece of evidence in seeking to understand this issue.

My current research has revealed though that there were two religious figures known in the 1st century who reportedly had a human mother and the supreme god as a father, but were not considered demi-gods. Both of these figures were associated with rising from the dead, women, slaves and rescuing their followers form the dark and desolate regions of the afterlife. Both also reportedly rode on a donkey at one significant point in time. The feasts for both involved bread and wine.

The worship of one had been banned by Rome in the 1st century BCE though, before Jesus was born. Also, this one who predated Jesus had been for some time linked by gentiles to the god of the Jews. If Paul's revelation was to link Jesus and this other entity to increase the popularity with the gentiles, it would also fit with his missionary journeys as this other entity had been greatly loved in the 1st century BCE in what is now Turkey and Greece.

However, I dare not say more with certainty as my research is ongoing. I wish to confirm that many, if not all, the issues Paul addressed in his letters can fit with the worship of this other entity as well as look for more positive signs that the linkage was made.

The revelation of Gal 2:2, 8 is the same one as in Eph 3:3, 6. It was a mystery. And what was it?

How that by revelation he made known unto me the mystery; (as I wrote afore in few words, … That the Gentiles should be fellowheirs, and of the same body, and partakers of his promise in Christ by the gospel:

And I went up by revelation, and communicated unto them that gospel which I preach among the Gentiles, but privately to them which were of reputation, lest by any means I should run, or had run, in vain. … (For he that wrought effectually in Peter to the apostleship of the circumcision, the same was mighty in me toward the Gentiles:)

The revelation was that the Gentiles were included in God's plan of redemption wholly apart from and independent of the Law of Moses.

By the time of Galatians 2:2, Paul had spent some 15 years in the ministry field, preaching first to the Jews and then primarily to the Gentiles. This work of spreading the Good News to whosoever will had reached back to the ears in Jerusalem. There were essentially two questions they had. The first was whether the gospel should even be preached to Gentiles and if so, whether it should be subjected to the Law of Moses.

Paul's revelation was that yes indeed through the seed of Abraham (Jesus Christ Gal 3:16) all nations might be blessed. Indeed, Christ's Great Commission had been ignored to a degree, but the message has been the same for some 6,000 years. Salvation is for all and is by grace through faith in the work of the Lord Jesus Christ (Eph 2:4-10).

The revelation wasn't to go to Jerusalem; the revelation had come earlier as the Holy Spirit worked on Paul to understood the Old Testament. As Paul heard about the resistance, as he understood that certain men did not like the Gentile inclusion into God's grace through Jesus Christ, he traveled back to Jerusalem. Because of the revelation first and the subsequent dilution second, go to the leaders and share the truth of the Gospel. All nations are blessed. You are saved by grace through faith in Christ Jesus.

The revelation was most likely simply a directive from God to go up to Jerusalem to talk with the apostles. This is the most natural way to read the verse, and there would be nothing surprising about this conclusion on the basis of the rest of Paul's life, since he was an apostle.

An apostle had to be someone who had seen Christ directly with his eyes. This is evidenced in the choosing of a replacement for Judas. It is also shown in this chapter itself; Paul is arguing that he has apostolic authority on the basis of the fact that he has had a revelation of Jesus Christ (1:11-12). Thus, he is an apostle not because he was sent by men, nor even commissioned by (authorized) men on behalf of God (this is the usual interpretation of 1:1). See also 1:16. Thus Paul says of himself elsewhere, "Last of all, as though I had been born at the wrong time, I also saw him."

Other examples of specific revelations he received:

• His conversion story, when he sees Christ face-to-face
• His apparent reference to himself in the "I know a man who has caught up into third heaven" passage
• His distinction in 1 Corinthians 7 between his own apostolic wisdom and the revelation he has directly from Jesus
• The Spirit's revelation to him of his sufferings in Jerusalem
• The Spirit's preventing him from going into Asia at one point (there may be a different interpretation of this)

Therefore, given that the Lord seems to have spoken to him not only at his conversion and not only to teach him doctrine, and given that the context is that he had been gone for fourteen years without seeing any need to go to Jerusalem (2:1), it seems extremely likely that the revelation was a specific direction that he ought to go up to Jerusalem and confer with the apostles, particularly James, Peter and John (2:9).